1. Field of the Invention
Aspects of the present invention relate to an organic light emitting diode. More particularly, aspects of the present invention relates to a multi-layer structure of the organic light emitting diode.
2. Description of the Related Art
Among various display panels for a display device, a display panel using an organic light emitting diode (OLED) has been receiving attention according to advances in semiconductor technology.
An active matrix type of OLED display using an organic light emitting diode includes a plurality of pixels arranged on a substrate in a matrix form and thin film transistors (TFTs) disposed at each of the pixels, such that each of the pixels is independently controlled through one of the thin film transistors.
In order to exhibit optimal characteristics of the OLED display, semiconductor elements including a thin film transistor and organic light emitting elements including an anode, a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), an electron injection layer (EIL), and a cathode should have good characteristics and should work well with each other.
Semiconductor elements are being actively studied and advances in technology with respect to semiconductor elements are being applied not only to the OLED displays but also to other technical systems. It would also be desirable to provide significant achievements through the study and development of the organic light emitting elements so that a satisfactory OLED display can be provided to a customer.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.